This invention relates to a pipe cutter, and in particular to a portable pipe cutter.
While the invention was specifically designed for cutting cement lined metal pipe, it will be appreciated that the pipe cutter can be used to cut pipes formed of virtually any conventional material.
Cement lined pipe has been in use for over twenty years in such areas as salt water injection lines and miscible flood systems in oil fields, and in municipal water systems. Such pipe is produced in diameters ranging from two to forty-two inches. The pipe is formed of a steel shell with a spun mortar liner. It is essential that pipe ends be cut accurately, so that welding can be effected with a minimum of damage to the cement.
Portable pipe cutters are disclosed, for example by Canadian Pat. No. 531,520, which issued to O. B. Harmes on Oct. 9, 1956, and U.S. Pat. Nos. 3,942,248, issued to C. R. Sherer et al on Mar. 9, 1976 and 4,213,357, issued to S. A. Lively et al on July 22, 1980. Devices currently available for cutting cement lined pipe include hand held grinders, the Wachs pipe guillotine saw, a milling machine, and a hand operated gas power saw. The hand held grinder was used in the early days of working with cement lined pipe as the only device for making a cut through the pipe. The process was slow, tedious and difficult, and accuracy was virtually impossible to achieve. The Wachs saw is manufactured by E. H. Wach Co., Wheeling, Ill., U.S.A. and consists of a powered, metal blade hack saw. The life of the blade is quite limited, and consequently the device is slow and expensive. The milling machine will cut and bevel a pipe accurately in a single operation by means of milling cutters formed of tungsten carbide. The life of the cutters is also quite limited. The gas power saw is similar in some respects to a chain saw used to cut wood. Cuts can be made relatively quickly, but are not sufficiently accurate for welding purposes. The pipe ends must be cleaned using a hand grinder, and consequently the entire cutting operation is somewhat lengthy.
The object of the present invention is to overcome the problems described above by providing a relatively simple pipe cutter, which facilitates accurate cutting of cement lined and other pipe, in any position from the horizontal to the vertical.